2 // literal.cs: Literal representation for the IL tree.
5 // Miguel de Icaza (miguel@ximian.com)
7 // (C) 2001 Ximian, Inc.
10 // Notice that during parsing we create objects of type Literal, but the
11 // types are not loaded (thats why the Resolve method has to assign the
12 // type at that point).
14 // Literals differ from the constants in that we know we encountered them
15 // as a literal in the source code (and some extra rules apply there) and
16 // they have to be resolved (since during parsing we have not loaded the
17 // types yet) while constants are created only after types have been loaded
18 // and are fully resolved when born.
22 using System.Reflection;
23 using System.Reflection.Emit;
26 // I put System.Null just so we do not have to special case it on
27 // TypeManager.CSharpName
31 // Represents the Null Type, just used as a placeholder for the type in NullLiteral
37 namespace Mono.CSharp {
40 // The NullType just exists to compare type equality, and for
41 // expressions that might have the `null type'
43 public class NullType {
47 // The null Literal constant
49 public class NullLiteral : Constant {
50 public static readonly NullLiteral Null;
54 Null = new NullLiteral ();
59 eclass = ExprClass.Value;
62 override public string AsString ()
67 public override object GetValue ()
72 public override Expression DoResolve (EmitContext ec)
74 type = TypeManager.null_type;
78 public override void Emit (EmitContext ec)
80 ec.ig.Emit (OpCodes.Ldnull);
83 public override bool IsDefaultValue {
89 public override bool IsNegative {
95 public override bool IsZeroInteger {
99 public override string GetSignatureForError()
104 public override void Error_ConstantValueCannotBeConverted (Location loc, Type t)
106 Report.Error (37, loc, "Cannot convert null to `{0}' because it is a value type",
107 TypeManager.CSharpName (t));
112 // A null literal in a pointer context
114 public class NullPointer : NullLiteral {
115 public new static readonly NullLiteral Null;
117 static NullPointer ()
119 Null = new NullPointer ();
122 private NullPointer ()
124 type = TypeManager.object_type;
127 public override void Emit (EmitContext ec)
129 ILGenerator ig = ec.ig;
131 ig.Emit (OpCodes.Ldc_I4_0);
132 ig.Emit (OpCodes.Conv_U);
136 public class BoolLiteral : BoolConstant {
137 public BoolLiteral (bool val) : base (val)
141 public override Expression DoResolve (EmitContext ec)
143 type = TypeManager.bool_type;
148 public class CharLiteral : CharConstant {
149 public CharLiteral (char c) : base (c)
153 public override Expression DoResolve (EmitContext ec)
155 type = TypeManager.char_type;
160 public class IntLiteral : IntConstant {
161 public static IntLiteral One, Zero;
165 Zero = new IntLiteral (0);
166 One = new IntLiteral (1);
169 public IntLiteral (int l) : base (l)
173 public override Expression DoResolve (EmitContext ec)
175 type = TypeManager.int32_type;
180 public class UIntLiteral : UIntConstant {
181 public UIntLiteral (uint l) : base (l)
185 public override Expression DoResolve (EmitContext ec)
187 type = TypeManager.uint32_type;
192 public class LongLiteral : LongConstant {
193 public LongLiteral (long l) : base (l)
197 public override Expression DoResolve (EmitContext ec)
199 type = TypeManager.int64_type;
205 public class ULongLiteral : ULongConstant {
206 public ULongLiteral (ulong l) : base (l)
210 public override Expression DoResolve (EmitContext ec)
212 type = TypeManager.uint64_type;
217 public class FloatLiteral : FloatConstant {
219 public FloatLiteral (float f) : base (f)
223 public override Expression DoResolve (EmitContext ec)
225 type = TypeManager.float_type;
230 public class DoubleLiteral : DoubleConstant {
231 public DoubleLiteral (double d) : base (d)
235 public override Expression DoResolve (EmitContext ec)
237 type = TypeManager.double_type;
243 public class DecimalLiteral : DecimalConstant {
244 public DecimalLiteral (decimal d) : base (d)
248 public override Expression DoResolve (EmitContext ec)
250 type = TypeManager.decimal_type;
255 public class StringLiteral : StringConstant {
256 public StringLiteral (string s) : base (s)
260 public override Expression DoResolve (EmitContext ec)
262 type = TypeManager.string_type;